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See detailPratiques émergentes et pensée du médium
Badir, Sémir ULg; Provenzano, François ULg

Book published by Academia-L'Harmattan (2017)

Qu’y a-t-il de commun entre le street art, les mooc ou les forums médicaux en ligne ? Il s’agit, dans tous les cas, de pratiques culturelles qui dépendent fortement des techniques qui en soutiennent ... [more ▼]

Qu’y a-t-il de commun entre le street art, les mooc ou les forums médicaux en ligne ? Il s’agit, dans tous les cas, de pratiques culturelles qui dépendent fortement des techniques qui en soutiennent l’émergence dans l’espace public. Le projet du présent volume est d’interroger ces pratiques émergentes pour la pensée médiatique qu’elles délivrent. La perspective d’analyse est sémiotique et se décline à travers une série d’études de cas qui cartographient notre imaginaire culturel contemporain. [less ▲]

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See detailAssessment of landslide hazard in the environmental hotspot areas of the Kyrgyz Tien-Shan: Spatial analysis and Numeric modelling
Torgoev, Almazbek ULg

Doctoral thesis (2017)

This PhD research was initiated in parallel with the Nato Science for Peace project “Prevention of Landslide Dam Disasters in the Tien Shan, Kyrgyz Republic”. During this project a large amount of ... [more ▼]

This PhD research was initiated in parallel with the Nato Science for Peace project “Prevention of Landslide Dam Disasters in the Tien Shan, Kyrgyz Republic”. During this project a large amount of thematic data on slope instabilities and landslide dams in the Kyrgyz Tien-Shan was collected. The thesis uses this information to investigate applied and fundamental aspects of the regional mapping of the landslide susceptibility, hazard and, partially, risk. The target areas selected for the PhD research are the Mailuu-Suu River Valley (southern Kyrgyzstan) and the surroundings of the Minkush settlement (central Kyrgyzstan). They represent the areas of former uranium mining hosting numerous storage sites of tailing material and waste rock. Additionally, these areas are characterised by a high level of landslide activity induced by the human and environmental impacts. The landslides in those areas present a high risk to the society and infrastructure, potentially triggering serious environmental consequences. Structurally, the thesis is composed of two parts: Part A and Part B. These parts are different both with respect to the research methodology and the scientific targets. The common goal of both parts is the development effective techniques to regionally assess landslide hazard in mountainous areas marked by complex geomorphological, tectonic and geological settings. Due to the remote access, such areas are often lacking background information and in-situ data that are required for the precise prediction of landslide occurrence and impacts. In such cases the spatial analysis often helps to better characterise regional and, partly, local landslide susceptibility. The regional studies allow us to outline the basic relationships between affecting factors and landslide occurrence. Such results also become the basis for effective planning of in-situ investigations and localised measurements. Part A of thesis is focused on the applied aspects of spatial analysis. This part assembles a set of the well-established approaches and methods to model landslide susceptibility, hazard and risk. The studies start with the compilation of database spatially combining various thematic information. The first type of such thematic data is represented by the multi-temporal landslide inventories. These inventories are extracted applying different sources of remote sensing data, including the satellite and aerial imagery. The second type of thematic data describes the spatial distribution of factors affecting the level of landslide activity. The mapping of affecting factors is performed by applying conventional remote sensing techniques and spatial analysis tools. The collected thematic data are then used to extract the landslide susceptibility, hazard and risk maps. In total, four conceptually different approaches are applied to map the landslide susceptibility, both on a qualitative and quantitative basis. The results of the quantitative susceptibility mapping and thematic data are further used to calculate the landslide hazard for each part of the studied area. The calculated landslide hazard is characterized both by spatial and temporal components. The results of the landslide hazard assessment are finally used to estimate the risk of the direct impacts of landslides on selected exposed elements, including the uranium tailings sites. One of the well-established approaches used in Part A is the Newmark method. It maps the seismically triggered landslide susceptibility based on the computed co-seismic displacements. The simplicity of this method is attractive to many researches around the world studying seismically-triggered landslide hazards. Nevertheless, the simplifications adopted in this method strongly limit the reliability of the final predictions. In the second part of thesis we provide a critical overview of the Newmark method and attempt to propose conceptual improvements of the existing mapping practice. To reach the targeted challenges we combine the spatial analysis with the dynamic simulations in the 2D and 3D domains. The studied models represent the actual topographic and geologic settings of the landslide-prone slopes. The simulations provide acceleration time histories that are recorded in different parts of the model surface. The analyses of these records allow us to outline the amplification impacts related to the topographic and geological site effects. The modelled amplification factors are analysed with respect to their link to the local geological and topographic settings. Thus, we study how the structural or material settings of the model can impact the recorded geological amplification. Such impacting parameters can be represented by the layer thickness, inclination of the underground contacts or the contrast of the shear wave velocity (Vs) values. The 2D topographic modelling investigates the way how the pure topographic amplification factors can be predicted based on the surface morphology. The studies show that the surface curvature can be considered as a key parameter to predict the amplification factors. This idea is further investigated in the 3D modelling studies applying different input signals and the materials of varying Vs. The results of this modelling are integrated into a single database which is subjected to spatial analysis. This finally allows us to develop a simple proxy which maps the impacts of the topographic site effects based on morphological parameters extracted from the Digital Elevation Model of the target area. Additionally, the subset of the 2D dynamic tests analyses the shear displacements triggered by the seismic shaking. Those displacements are recorded in the models with simplified geometry, as well as in the ones presenting the real topographic settings. The recorded displacements are cross-correlated with parameters characterising the seismic impacts. The results of analyses allow us to develop a new law which can easily be used in the GIS-based studies. The proposed law applies a set of the conventional parameters as well as a novel predictor which has never been used by any regional law before.The conceptual improvements proposed in Part B are finally tested by applying them to the geodatabase compiled in the first part of thesis. Related results are then compared with those that were produced by using the conventional Newmark method. The validation tests should assess performance of the developed proxies to improve the predictions of seismically-triggered landslides. [less ▲]

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See detailEnhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands: a sink for atmospheric CO2
Wan, Shiming; Clift, Peter D.; Zhao, Debo et al

in Geochimica et Cosmochimica Acta (2017), 200

Atmospheric CO2 and global climate are closely coupled. Since 800 ka CO2 concentrations have been up to 50% higher during interglacial compared to glacial periods. Because of its dependence on temperature ... [more ▼]

Atmospheric CO2 and global climate are closely coupled. Since 800 ka CO2 concentrations have been up to 50% higher during interglacial compared to glacial periods. Because of its dependence on temperature, humidity, and erosion rates, chemical weathering of exposed silicate minerals was suggested to have dampened these cyclic variations of atmospheric composition. Cooler and drier conditions and lower non-glacial erosion rates suppressed in situ chemical weathering rates during glacial periods. However, using systematic variations in major element geochemistry, Sr-Nd isotopes and clay mineral records from Ocean Drilling Program Sites 1143 and 1144 in the South China Sea spanning the last 1.1 Ma, we show that sediment deposited during glacial periods was more weathered than sediment delivered during interglacials. We attribute this to subaerial exposure and weathering of unconsolidated shelf sediments during glacial sealevel lowstands. Our estimates suggest that enhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands can account for ~9% of the carbon dioxide removed from the atmosphere during the glacial and thus represent a significant part of the observed glacial-interglacial variation of ~80 ppmv. As a result, if similar magnitudes can be identified in other tropical shelf-slope systems, the effects of increased sediment exposure and subsequent silicate weathering during lowstands could have potentially enhanced the drawdown of atmospheric CO2 during cold stages of the Quaternary. This in turn would have caused an intensification of glacial cycles. We attribute this to subaerial exposure and weathering of unconsolidated shelf sediments during glacial sealevel lowstands. Our estimates suggest that enhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands can account for ~9% of the carbon dioxide removed from the atmosphere during the glacial and thus represent a significant part of the observed glacial-interglacial variation of ~80 ppmv. As a result, if similar magnitudes can be identified in other tropical shelf-slope systems, the effects of increased sediment exposure and subsequent silicate weathering during lowstands could have potentially enhanced the drawdown of atmospheric CO2 during cold stages of the Quaternary. This in turn would have caused an intensification of glacial cycles. [less ▲]

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See detailLa « discrimination à rebours » au sein du marché intérieur : une illégalité qu’il ne faut pas voir au niveau européen ?
Van Cleynenbreugel, Pieter ULg

in Revue de la Faculté de Droit de l'Université de Liège (2017)

Cet article dresse un panorama de la jurisprudence sur les situations purement internes au droit du marché intérieur et du phénomène juridique de la discrimination à rebours. Il est conclu qu'une telle ... [more ▼]

Cet article dresse un panorama de la jurisprudence sur les situations purement internes au droit du marché intérieur et du phénomène juridique de la discrimination à rebours. Il est conclu qu'une telle discrimination est inhérente au régime juridique de l'Union européenne caractérisé par le principe d'attribution des compétences. Il convient aux Etats membres d'y apporter des solutions fondées sur leurs droits constitutionnels respectifs. [less ▲]

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See detailLe non bis in idem en droit de la concurrence : un monde de différence avec le pénal ?
Van Cleynenbreugel, Pieter ULg

in Franssen, Vanessa; Thiel, Delphine (Eds.) EXISTE-T-IL ENCORE UN SEUL NON BIS IN IDEM AUJOURD'HUI ? (2017)

Ce chapitre analyse l'application du principe de non bis in idem dans le contexte du droit européen de la concurrence, la comparant aux applications du même principes dans de domaines connexes.

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See detailArtefact présente Tante Leny. L'underground hollandaise importée en France
Crucifix, Benoît ULg

Article for general public (2017)

Brève analyse du rôle de passeur culturel joué par Artefact dans leurs traductions de la bande dessinée underground hollandaise, via le collectif Tante Leny presenteert!.

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See detail'Mourning and Metafiction in Peter Carey's Chemistry of Tears'
Delrez, Marc ULg

in Collier, G, Davis, G; Ledent, B (Eds.) The Cross-Cultural Legacy: Critical and Creative Writings in Memory of Hena Maes-Jelinek (2017)

Peter Carey’s recent novel shares the concern with ‘unoriginality’ which has become a hallmark of his later fiction. It can actually be argued that, through this new variation on a known theme, he ... [more ▼]

Peter Carey’s recent novel shares the concern with ‘unoriginality’ which has become a hallmark of his later fiction. It can actually be argued that, through this new variation on a known theme, he purports to move beyond the clichéd postmodern paradox that authenticities – whether psychological or aesthetic – are always essentially made up, in order to consider the matter from another angle, pondering the perilous moment when an overtly fabricated object somehow mysteriously springs to life. If, as the title suggests, even our most personal emotions can be rationalized in terms of chemical reactions, why then could we not pursue a reverse path of investigation and envisage material reality as the source providing the components for the creation of spirit? This is the subjective context in which the protagonist Catherine, who works as a horologist (clockwork expert) in a London museum, must reconstruct a nineteenth-century mechanical swan suspected by some to be harbouring the soul of its original maker. Interestingly Catherine, herself a die-hard rationalist, finds herself shaken by a devastating bereavement which makes her unusually open to any form of consolation – including the self-indulgence of nostalgia, but also of cocaine and alcohol – which is why she will whole-heartedly embrace the welcome distraction offered by her work of mechanical reconstruction. As part of her attempt to understand the structure of the automaton, she feels that she must immerse herself in the diaries left behind by the commissioner of the work, an Englishman named Henry Brandling animated by his faith that the elaborate toy may release enough energy in his consumptive son, Percy, to save him from his otherwise lethal condition. Thus Carey creates an opening into the rationalist fabric of his protagonist’s present, allowing her to entertain anachronistic fantasies about the life-saving (let alone life-giving) properties of true art. Inasmuch as Catherine’s perusal of the diaries eventually facilitates a circuitous confrontation of her own grief, so that her excursions into the past serve to shore up her fragile sense of a future, the text appears to vindicate its own fantastic claims about the demiurgic, or at least redemptive, powers of art. Perhaps predictably, some reviewers balked in the face of this species of self-promotion, repeating the oft-expressed view that Carey’s fiction, in view of its deliberate straining of the laws of credibility, finally fails to emerge from an enmeshment in its own favoured themes of forgery and imitative inadequacy. The ultimate question asked by the work is then whether it must be seen to be equal to its own promise of transcendence. The present paper, by way of its own descent into the past (and particularly through a comparison with My Life as a Fake which rehearses similar themes), will try to provide an answer, notably by circumscribing the intention of a text in which metafiction assumes a metaphysical dimension possibly unique in Carey’s corpus. [less ▲]

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See detailLa mise en œuvre du droit de plainte en Belgique francophone. Observation des processus de médiation en soins de santé
Dubois, Christophe ULg; Vandeninden, Elise ULg

in Revue Française des Affaires Sociales (2017), 1(1), 79-96

This article concerns the treatment of patients’ rights cases in French‐speaking Belgian hospitals by the “mediator”, that is, the person who has the legal duty of dealing with grievances arising from the ... [more ▼]

This article concerns the treatment of patients’ rights cases in French‐speaking Belgian hospitals by the “mediator”, that is, the person who has the legal duty of dealing with grievances arising from the application of this right of complaint. What happens to a patient’s complaint? This is the question that this article attempts to answer through a report on the “local” organization of mediation ser‐ vices within the hospital. It thus clari es the links and divergences between the formal discourses accompanying the implementation of the mediation function in health care on the one hand, and, on the other hand, the actual practices of media‐ tion determined by the work of mediators in the hospital. [less ▲]

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See detailMachine Learning of Real-time Power Systems Reliability Management Response
Duchesne, Laurine ULg; Karangelos, Efthymios ULg; Wehenkel, Louis ULg

in PowerTech Manchester 2017 Proceedings (2017)

In this paper we study how supervised machine learning could be applied to build simplified models of real-time (RT) reliability management response to the realization of uncertainties. The final ... [more ▼]

In this paper we study how supervised machine learning could be applied to build simplified models of real-time (RT) reliability management response to the realization of uncertainties. The final objective is to import these models into look-ahead operation planning under uncertainties. Our response models predict in particular the real-time reliability management costs and the resulting reliability level of the system. We tested our methodology on the IEEE-RTS96 benchmark. Among the supervised learning algorithms tested, extremely randomized trees, kernel ridge regression and neural networks appear to be the best methods for this application. Furthermore, by using feature “importances” computed by tree-based ensemble methods, we were able to extract the most relevant variables to predict the response of real-time reliability management, and thus obtain a better understanding of the system properties. [less ▲]

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See detailMicrostructural and functional correlates of glutamate concentration in the posterior cingulate cortex.
Arrubla Martinez, Jorge Andres ULg; Farrher, Ezequiel; Strippelmann, Johanna et al

in Journal of Neuroscience Research (2017)

Glutamate is the major excitatory neurotransmitter in the human brain and has a central role in both intrinsic and stimulus-induced activity. We conducted a study in a cohort of healthy, male volunteers ... [more ▼]

Glutamate is the major excitatory neurotransmitter in the human brain and has a central role in both intrinsic and stimulus-induced activity. We conducted a study in a cohort of healthy, male volunteers in which glutamate levels were measured in the posterior cingulate cortex (PCC) using 1H magnetic resonance spectroscopy at 3T. The advantages of simultaneous electroencephalography and magnetic resonance imaging (EEG-MRI) were exploited and the subjects were measured in the same session and under the same physiological conditions. Diffusion tensor imaging (DTI), functional MRI (fMRI) and EEG were measured in order to investigate the functional and microstructural correlates of glutamate. The concentration of glutamate (institute units) was calculated and those values were tested for correlation with the metrics of resting state fMRI, DTI, and EEG electrical sources. Our results showed that the concentration of glutamate in the PCC had a significant negative correlation with the tissue mean diffusivity in the same area. The analysis of resting state networks did not show any relationship between the concentration of glutamate and the intrinsic activity of the resting state networks. The concentration of glutamate showed a positive correlation with the electrical generators of alpha-1 frequency and a negative correlation with the generators of alpha-2 and beta-1 electrical generators. (c) 2017 Wiley Periodicals, Inc. [less ▲]

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See detailFlux penetration in a superconducting film partially capped with a conducting layer
Brisbois, Jérémy ULg; Gladilin, V. N.; Tempere, J. et al

in Physical Review B (2017)

The influence of a conducting layer on the magnetic flux penetration in a superconducting Nb film is studied by magneto-optical imaging. The metallic layer partially covering the superconductor provides ... [more ▼]

The influence of a conducting layer on the magnetic flux penetration in a superconducting Nb film is studied by magneto-optical imaging. The metallic layer partially covering the superconductor provides an additional velocity-dependent damping mechanism for the flux motion that helps protecting the superconducting state when thermomagnetic instabilities develop. If the flux advances with a velocity slower than w = 2/µ0σt, where σ is the cap layer conductivity and t is its thickness, the flux penetration remains unaffected, whereas for incoming flux moving faster than w, the metallic layer becomes an active screening shield. When the metallic layer is replaced by a perfect conductor, it is expected that the flux braking effect will occur for all flux velocities. We demonstrate this effect by investigating Nb samples with a thickness step. Some of the observed features, namely the deflection and the branching of the flux trajectories at the border of the thick centre, as well as the favoured flux penetration at the indentation, are reproduced by time-dependent Ginzburg-Landau simulations. [less ▲]

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See detailTumor host-interface in metastatic dissemination and adaptation to treatment
Sounni, Nor Eddine ULg

Scientific conference (2017)

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See detailMethylglyoxal-Mediated Stress Correlates with High Metabolic Activity and Promotes Tumor Growth in Colorectal Cancer.
Chiavarina, Barbara ULg; Nokin, Marie-Julie ULg; Bellier, Justine ULg et al

in International Journal of Molecular Sciences (2017), 18(1),

Cancer cells generally rely on aerobic glycolysis as a major source of energy. Methylglyoxal (MG), a dicarbonyl compound that is produced as a side product during glycolysis, is highly reactive and ... [more ▼]

Cancer cells generally rely on aerobic glycolysis as a major source of energy. Methylglyoxal (MG), a dicarbonyl compound that is produced as a side product during glycolysis, is highly reactive and induces the formation of advanced glycation end-products that are implicated in several pathologies including cancer. All mammalian cells have an enzymatic defense against MG composed by glyoxalases GLO1 and GLO2 that converts MG to d-lactate. Colorectal cancer (CRC) is one of the most frequently occurring cancers with high morbidity and mortality. In this study, we used immunohistochemistry to examine the level of MG protein adducts, in a series of 102 CRC human tumors divided into four clinical stages. We consistently detected a high level of MG adducts and low GLO1 activity in high stage tumors compared to low stage ones suggesting a pro-tumor role for dicarbonyl stress. Accordingly, GLO1 depletion in CRC cells promoted tumor growth in vivo that was efficiently reversed using carnosine, a potent MG scavenger. Our study represents the first demonstration that MG adducts accumulation is a consistent feature of high stage CRC tumors. Our data point to MG production and detoxification levels as an important molecular link between exacerbated glycolytic activity and CRC progression. [less ▲]

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See detailThe role of parental anxiety sensitivity and learning experiences in children's anxiety sensitivity.
Stassart, Céline ULg; Dardenne, Benoît ULg; Etienne, Anne-Marie ULg

in British Journal of Developmental Psychology (2017)

This study evaluated the impact of the mother’s and father’s anxiety sensitivity (AS) andlearning experiences on children’s AS, and the influence of two moderators: the children’sfemininity orientation and ... [more ▼]

This study evaluated the impact of the mother’s and father’s anxiety sensitivity (AS) andlearning experiences on children’s AS, and the influence of two moderators: the children’sfemininity orientation and the children’s emotional intelligence (EI). The samplecomprised 200 non-clinical children, aged 9–13 years, and their parents (mothers andfathers). Results revealed that the effect of parental AS on children’s AS is moderated bythe children’s EI for maternal AS and by their femininity traits for paternal AS. Learningexperiences following somatic sensations influenced the children’s level of AS. Morespecifically, special attention by parents following a child’s somatic sensations (reinforce-ment and transmission of information) was associated with high AS in children. Parentalreactions of fear following a parent’s somatic sensations (modelling) seem to predicthigher scores for AS when the link is moderated by the child’s femininity orientation. Theimplications of these findings are discussed. [less ▲]

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See detailGlobal disorders of consciousness.
Stender, Johan; Laureys, Steven ULg; Gosseries, Olivia ULg

in Velmans, Max; Schneider, Susan (Eds.) The Blackwell Companion to Consciousness (2017)

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See detailPotential uses of pumped urban groundwater. A case study in Sant Adrià del Besòs (Spain)
Jurado Elices, Anna ULg; vázquez-Suñé, Enric; Pujades, Estanislao ULg

in Hydrogeology Journal (2017)

Urban groundwater has been over-exploited during the past, mainly for industrial uses, and it now tends to be reduced or abandoned due to pollution and/or changes in land use. The use and the subsequent ... [more ▼]

Urban groundwater has been over-exploited during the past, mainly for industrial uses, and it now tends to be reduced or abandoned due to pollution and/or changes in land use. The use and the subsequent disuse of groundwater resulted in rising water tables that damage underground structures (e.g., building basements and underground car parks and tunnels), leading to additional pumping in urban areas. This is the case of the underground parking lot of Sant Adrià del Besòs (NE Spain), where large amounts of urban groundwater are pumped to avoid seepage problems. The question that arises here is if this pumped groundwater can be used for other purposes (e.g., drinking water and urban irrigation) instead of wasting this valuable resource. To answer this question, it is necessary to quantify the groundwater recharge and to assess the evolution of ground-water quality in order to properly identify its potential uses. The limiting factor to define the uses of this resource is the groundwater quality because ammonium and some metals (iron and manganese) are present at high concentrations. Hence, further treatment would be needed to meet drinking water requirements. The pumped groundwater could also be used for supplying the ecological river flow and/or for mitigating seawater intrusion problems. Currently, only a small amount of this urban groundwater is used for cleaning public areas and watering public gardens. This situation highlighted the urgent need to manage this resource in a responsible and more efficient manner, especially in moments of high water demand such as drought periods. [less ▲]

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See detailMono- and bimetallic manganese-carbonyl complexes and clusters bearing imidazol(in)ium-2-dithiocarboxylate ligands
Beltran Alvarez, Tomás Francisco ULg; Zaragoza, Guillermo; Delaude, Lionel ULg

in Dalton Transactions (2017), 46

Five complexes with the generic formula fac-[MnBr(CO)3(S2C[middle dot]NHC)] were obtained by reacting [MnBr(CO)5] with a set of representative imidazol(in)ium-2-dithiocarboxylate zwitterions. These ... [more ▼]

Five complexes with the generic formula fac-[MnBr(CO)3(S2C[middle dot]NHC)] were obtained by reacting [MnBr(CO)5] with a set of representative imidazol(in)ium-2-dithiocarboxylate zwitterions. These ligands are the adducts of N-heterocyclic carbenes (NHCs) and carbon disulfide. The mononuclear Mn(i) derivatives were coupled with Na[Mn(CO)5] to afford bimetallic [Mn2(CO)6(S2C[middle dot]NHC)] clusters. Yet, the most convenient strategy to access these dinuclear Mn(0) products implied a direct carbonyl substitution from the [Mn2(CO)10] dimer. The molecular structures of three monometallic and four bimetallic compounds were elucidated by single crystal X-ray diffraction analysis. In the monometallic complexes, the NHC[middle dot]CS2 ligands exhibited a bidentate [small kappa]2-S,S[prime or minute] coordination mode with an S-C-S bite angle of about 116[degree]. In the dinuclear clusters, the CS2- unit acted as a chelate toward one manganese center and as a pseudoallylic ligand toward the other one. The S-C-S bite angle was reduced to ca. 104[degree]. Thus, the zwitterions displayed a remarkable flexibility, which also permitted a staggered arrangement of the carbonyl groups in the bimetallic systems. Examination of the [small nu, Greek, macron]CO absorption bands on IR spectroscopy helped identify the presence of fac-Mn(CO)3 or Mn2(CO)6 motifs, while the 13C NMR chemical shift of the CS2- moiety was a reliable indicator for monitoring its hapticity. Whereas the dinuclear clusters were air- and moisture-stable crystalline solids, mononuclear halido derivatives displayed only a limited stability under aerobic conditions. Both types of compounds underwent rather unselective, extensive fragmentations in the gas phase, in sharp contrast with the analogous rhenium derivatives that led to clean sequential decarbonylation processes upon collision-induced dissociation. [less ▲]

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